I found this study to be rather interesting. It compares crop yield with various fertilizing practices. Just NPK in soil, microbe applications, compost in soil, and compost in soil plus microbe applications. Although the study doesn't have enough information to prove the same nutrient amounts were used for each practice (NPK vs compost more particularly) its results are interesting. -Microbes alone had less yield than NPK -Compost alone had less yield than NPK -Compost + microbes had in INCREASE in yield compared to NPK The conclusion suggests some reasons for it but fails to mention one suspicion I have, the microbes help to unlock Organic N in the compost thus the compost and microbes were most effective at making nutrients available to plants. What are your thoughts?